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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  
20  package org.apache.myfaces.orchestra.conversation.jsf.components.facelets;
21  
22  import com.sun.facelets.FaceletContext;
23  import com.sun.facelets.FaceletException;
24  import com.sun.facelets.tag.TagAttribute;
25  import com.sun.facelets.tag.TagConfig;
26  import com.sun.facelets.tag.TagHandler;
27  import org.apache.myfaces.orchestra.lib.jsf.SerializableConverter;
28  
29  import javax.el.ELException;
30  import javax.faces.FacesException;
31  import javax.faces.application.Application;
32  import javax.faces.component.EditableValueHolder;
33  import javax.faces.component.UIComponent;
34  import javax.faces.context.FacesContext;
35  import javax.faces.convert.Converter;
36  import java.io.IOException;
37  
38  public class ConverterTagHandler extends TagHandler
39  {
40      private final TagAttribute beanName;
41      private final TagAttribute useWrapper;
42  
43      public ConverterTagHandler(TagConfig config)
44      {
45          super(config);
46          beanName = getRequiredAttribute("beanName"); // NON-NLS
47          useWrapper = getAttribute("useWrapper"); // NON-NLS
48      }
49  
50      public void apply(FaceletContext faceletContext, UIComponent parent)
51      throws IOException, FacesException, FaceletException, ELException
52      {
53          if (parent.getParent() == null)
54          {
55              if (parent instanceof EditableValueHolder)
56              {
57                  Converter converter = createConverter(beanName.getValue());
58  
59                  if (useWrapper == null || !"false".equals(useWrapper.getValue()) &&
60                      !(converter instanceof SerializableConverter))
61                  {
62                      // Needed to check if it is already of the specified type in case the
63                      // managed-bean framework has been configured to auto-wrap Converter
64                      // instances already (eg via a Spring BeanPostProcessor or equivalent).
65                      // This isn't the case, so wrap it now.
66                      converter = new SerializableConverter(beanName.getValue(), converter);
67                  }
68  
69                  ((EditableValueHolder) parent).setConverter(converter);
70              }
71              else
72              {
73                  throw new FacesException("parent is not an EditableValueHolder");
74              }
75          }
76      }
77  
78      /**
79       * Override this method in order to customise the bean instance.
80       */
81      protected static Converter createConverter(String beanName)
82      {
83          FacesContext facesContext = FacesContext.getCurrentInstance();
84          Application application = facesContext.getApplication();
85          Object converter = application.getVariableResolver().resolveVariable(facesContext, beanName);
86          return (Converter) converter;
87      }
88  }